What is the best way to keep powdery kief powdery after I decarboxylate it? Thank you.
Good question and like many things associated with cannabis cooking, it depends.
That's because there are so many different textures when it comes to kief, depending on the plant material it is made from. Some are powerdy kiefs, but others can get sticky, especially if it's good kief. Some kief can even be gummy after decarboxylation (the process of heating the kief into order to transform the plant's THC-A into psychoactive THC).
You can see the difference in the raw kief in the photo at the top of this page, and the decarbed kief in the photo to the right here. The decarbed kief is dryer and more dense.
If it started as really powdery kief, sometimes you can crush it into a powder with your fingers. I was able to do that with the kief in the photo at right, as you can see it barely clumped together after decarbing.
Otherwise I usually use a mortar and pestle to gently break up the decarbed kief before adding to a recipe. Use a gentle hand as, if your kief is gummy, a hard mashing could make the problem worse and cement it together. But for many varieties a gentle crushing in a mortar and pestle will work. Alternately the back of a spoon on a small plate can get you a similar result.
For dry varieties a fine grater or microplaner can also do the trick, but most kief is already too crumbly for this, but I have seen some varieties where this works. Again, providing it is not too gummy, cause if it is too gummy it will just make a mess of the grater.
If your kief is ultra gummy, I try to save this type for use in recipes and foods that call for heating. Heated in liquids, most, if not all of the kief will dissolve and disappear into the foods. Even the sticky, gummy variety.
No matter what the variety, I do the crushing, mashing, etc. right before adding to the recipe. That's cause if you do it sooner, depending on the temperature and how the kief is stored, it can clump back together again.
Hope this helps.